drivers/mtd/nand/raw/nandsim.c

   1 /*
   2  * NAND flash simulator.
   3  *
   4  * Author: Artem B. Bityuckiy <[email protected]>, <[email protected]>
   5  *
   6  * Copyright (C) 2004 Nokia Corporation
   7  *
   8  * Note: NS means "NAND Simulator".
   9  * Note: Input means input TO flash chip, output means output FROM chip.
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU General Public License as published by the
  13  * Free Software Foundation; either version 2, or (at your option) any later
  14  * version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
  19  * Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
  24  */
  25
  26 #define pr_fmt(fmt)  "[nandsim]" fmt
  27
  28 #include <linux/init.h>
  29 #include <linux/types.h>
  30 #include <linux/module.h>
  31 #include <linux/moduleparam.h>
  32 #include <linux/vmalloc.h>
  33 #include <linux/math64.h>
  34 #include <linux/slab.h>
  35 #include <linux/errno.h>
  36 #include <linux/string.h>
  37 #include <linux/mtd/mtd.h>
  38 #include <linux/mtd/rawnand.h>
  39 #include <linux/mtd/nand_bch.h>
  40 #include <linux/mtd/partitions.h>
  41 #include <linux/delay.h>
  42 #include <linux/list.h>
  43 #include <linux/random.h>
  44 #include <linux/sched.h>
  45 #include <linux/sched/mm.h>
  46 #include <linux/fs.h>
  47 #include <linux/pagemap.h>
  48 #include <linux/seq_file.h>
  49 #include <linux/debugfs.h>
  50
  51 /* Default simulator parameters values */
  52 #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE)  || \
  53     !defined(CONFIG_NANDSIM_SECOND_ID_BYTE) || \
  54     !defined(CONFIG_NANDSIM_THIRD_ID_BYTE)  || \
  55     !defined(CONFIG_NANDSIM_FOURTH_ID_BYTE)
  56 #define CONFIG_NANDSIM_FIRST_ID_BYTE  0x98
  57 #define CONFIG_NANDSIM_SECOND_ID_BYTE 0x39
  58 #define CONFIG_NANDSIM_THIRD_ID_BYTE  0xFF /* No byte */
  59 #define CONFIG_NANDSIM_FOURTH_ID_BYTE 0xFF /* No byte */
  60 #endif
  61
  62 #ifndef CONFIG_NANDSIM_ACCESS_DELAY
  63 #define CONFIG_NANDSIM_ACCESS_DELAY 25
  64 #endif
  65 #ifndef CONFIG_NANDSIM_PROGRAMM_DELAY
  66 #define CONFIG_NANDSIM_PROGRAMM_DELAY 200
  67 #endif
  68 #ifndef CONFIG_NANDSIM_ERASE_DELAY
  69 #define CONFIG_NANDSIM_ERASE_DELAY 2
  70 #endif
  71 #ifndef CONFIG_NANDSIM_OUTPUT_CYCLE
  72 #define CONFIG_NANDSIM_OUTPUT_CYCLE 40
  73 #endif
  74 #ifndef CONFIG_NANDSIM_INPUT_CYCLE
  75 #define CONFIG_NANDSIM_INPUT_CYCLE  50
  76 #endif
  77 #ifndef CONFIG_NANDSIM_BUS_WIDTH
  78 #define CONFIG_NANDSIM_BUS_WIDTH  8
  79 #endif
  80 #ifndef CONFIG_NANDSIM_DO_DELAYS
  81 #define CONFIG_NANDSIM_DO_DELAYS  0
  82 #endif
  83 #ifndef CONFIG_NANDSIM_LOG
  84 #define CONFIG_NANDSIM_LOG        0
  85 #endif
  86 #ifndef CONFIG_NANDSIM_DBG
  87 #define CONFIG_NANDSIM_DBG        0
  88 #endif
  89 #ifndef CONFIG_NANDSIM_MAX_PARTS
  90 #define CONFIG_NANDSIM_MAX_PARTS  32
  91 #endif
  92
  93 static uint access_delay   = CONFIG_NANDSIM_ACCESS_DELAY;
  94 static uint programm_delay = CONFIG_NANDSIM_PROGRAMM_DELAY;
  95 static uint erase_delay    = CONFIG_NANDSIM_ERASE_DELAY;
  96 static uint output_cycle   = CONFIG_NANDSIM_OUTPUT_CYCLE;
  97 static uint input_cycle    = CONFIG_NANDSIM_INPUT_CYCLE;
  98 static uint bus_width      = CONFIG_NANDSIM_BUS_WIDTH;
  99 static uint do_delays      = CONFIG_NANDSIM_DO_DELAYS;
 100 static uint log            = CONFIG_NANDSIM_LOG;
 101 static uint dbg            = CONFIG_NANDSIM_DBG;
 102 static unsigned long parts[CONFIG_NANDSIM_MAX_PARTS];
 103 static unsigned int parts_num;
 104 static char *badblocks = NULL;
 105 static char *weakblocks = NULL;
 106 static char *weakpages = NULL;
 107 static unsigned int bitflips = 0;
 108 static char *gravepages = NULL;
 109 static unsigned int overridesize = 0;
 110 static char *cache_file = NULL;
 111 static unsigned int bbt;
 112 static unsigned int bch;
 113 static u_char id_bytes[8] = {
 114         [0] = CONFIG_NANDSIM_FIRST_ID_BYTE,
 115         [1] = CONFIG_NANDSIM_SECOND_ID_BYTE,
 116         [2] = CONFIG_NANDSIM_THIRD_ID_BYTE,
 117         [3] = CONFIG_NANDSIM_FOURTH_ID_BYTE,
 118         [4 ... 7] = 0xFF,
 119 };
 120
 121 module_param_array(id_bytes, byte, NULL, 0400);
 122 module_param_named(first_id_byte, id_bytes[0], byte, 0400);
 123 module_param_named(second_id_byte, id_bytes[1], byte, 0400);
 124 module_param_named(third_id_byte, id_bytes[2], byte, 0400);
 125 module_param_named(fourth_id_byte, id_bytes[3], byte, 0400);
 126 module_param(access_delay,   uint, 0400);
 127 module_param(programm_delay, uint, 0400);
 128 module_param(erase_delay,    uint, 0400);
 129 module_param(output_cycle,   uint, 0400);
 130 module_param(input_cycle,    uint, 0400);
 131 module_param(bus_width,      uint, 0400);
 132 module_param(do_delays,      uint, 0400);
 133 module_param(log,            uint, 0400);
 134 module_param(dbg,            uint, 0400);
 135 module_param_array(parts, ulong, &parts_num, 0400);
 136 module_param(badblocks,      charp, 0400);
 137 module_param(weakblocks,     charp, 0400);
 138 module_param(weakpages,      charp, 0400);
 139 module_param(bitflips,       uint, 0400);
 140 module_param(gravepages,     charp, 0400);
 141 module_param(overridesize,   uint, 0400);
 142 module_param(cache_file,     charp, 0400);
 143 module_param(bbt,            uint, 0400);
 144 module_param(bch,            uint, 0400);
 145
 146 MODULE_PARM_DESC(id_bytes,       "The ID bytes returned by NAND Flash 'read ID' command");
 147 MODULE_PARM_DESC(first_id_byte,  "The first byte returned by NAND Flash 'read ID' command (manufacturer ID) (obsolete)");
 148 MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID) (obsolete)");
 149 MODULE_PARM_DESC(third_id_byte,  "The third byte returned by NAND Flash 'read ID' command (obsolete)");
 150 MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command (obsolete)");
 151 MODULE_PARM_DESC(access_delay,   "Initial page access delay (microseconds)");
 152 MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds");
 153 MODULE_PARM_DESC(erase_delay,    "Sector erase delay (milliseconds)");
 154 MODULE_PARM_DESC(output_cycle,   "Word output (from flash) time (nanoseconds)");
 155 MODULE_PARM_DESC(input_cycle,    "Word input (to flash) time (nanoseconds)");
 156 MODULE_PARM_DESC(bus_width,      "Chip's bus width (8- or 16-bit)");
 157 MODULE_PARM_DESC(do_delays,      "Simulate NAND delays using busy-waits if not zero");
 158 MODULE_PARM_DESC(log,            "Perform logging if not zero");
 159 MODULE_PARM_DESC(dbg,            "Output debug information if not zero");
 160 MODULE_PARM_DESC(parts,          "Partition sizes (in erase blocks) separated by commas");
 161 /* Page and erase block positions for the following parameters are independent of any partitions */
 162 MODULE_PARM_DESC(badblocks,      "Erase blocks that are initially marked bad, separated by commas");
 163 MODULE_PARM_DESC(weakblocks,     "Weak erase blocks [: remaining erase cycles (defaults to 3)]"
 164                                  " separated by commas e.g. 113:2 means eb 113"
 165                                  " can be erased only twice before failing");
 166 MODULE_PARM_DESC(weakpages,      "Weak pages [: maximum writes (defaults to 3)]"
 167                                  " separated by commas e.g. 1401:2 means page 1401"
 168                                  " can be written only twice before failing");
 169 MODULE_PARM_DESC(bitflips,       "Maximum number of random bit flips per page (zero by default)");
 170 MODULE_PARM_DESC(gravepages,     "Pages that lose data [: maximum reads (defaults to 3)]"
 171                                  " separated by commas e.g. 1401:2 means page 1401"
 172                                  " can be read only twice before failing");
 173 MODULE_PARM_DESC(overridesize,   "Specifies the NAND Flash size overriding the ID bytes. "
 174                                  "The size is specified in erase blocks and as the exponent of a power of two"
 175                                  " e.g. 5 means a size of 32 erase blocks");
 176 MODULE_PARM_DESC(cache_file,     "File to use to cache nand pages instead of memory");
 177 MODULE_PARM_DESC(bbt,            "0 OOB, 1 BBT with marker in OOB, 2 BBT with marker in data area");
 178 MODULE_PARM_DESC(bch,            "Enable BCH ecc and set how many bits should "
 179                                  "be correctable in 512-byte blocks");
 180
 181 /* The largest possible page size */
 182 #define NS_LARGEST_PAGE_SIZE    4096
 183
 184 /* Simulator's output macros (logging, debugging, warning, error) */
 185 #define NS_LOG(args...) \
 186         do { if (log) pr_debug(" log: " args); } while(0)
 187 #define NS_DBG(args...) \
 188         do { if (dbg) pr_debug(" debug: " args); } while(0)
 189 #define NS_WARN(args...) \
 190         do { pr_warn(" warning: " args); } while(0)
 191 #define NS_ERR(args...) \
 192         do { pr_err(" error: " args); } while(0)
 193 #define NS_INFO(args...) \
 194         do { pr_info(" " args); } while(0)
 195
 196 /* Busy-wait delay macros (microseconds, milliseconds) */
 197 #define NS_UDELAY(us) \
 198         do { if (do_delays) udelay(us); } while(0)
 199 #define NS_MDELAY(us) \
 200         do { if (do_delays) mdelay(us); } while(0)
 201
 202 /* Is the nandsim structure initialized ? */
 203 #define NS_IS_INITIALIZED(ns) ((ns)->geom.totsz != 0)
 204
 205 /* Good operation completion status */
 206 #define NS_STATUS_OK(ns) (NAND_STATUS_READY | (NAND_STATUS_WP * ((ns)->lines.wp == 0)))
 207
 208 /* Operation failed completion status */
 209 #define NS_STATUS_FAILED(ns) (NAND_STATUS_FAIL | NS_STATUS_OK(ns))
 210
 211 /* Calculate the page offset in flash RAM image by (row, column) address */
 212 #define NS_RAW_OFFSET(ns) \
 213         (((ns)->regs.row * (ns)->geom.pgszoob) + (ns)->regs.column)
 214
 215 /* Calculate the OOB offset in flash RAM image by (row, column) address */
 216 #define NS_RAW_OFFSET_OOB(ns) (NS_RAW_OFFSET(ns) + ns->geom.pgsz)
 217
 218 /* After a command is input, the simulator goes to one of the following states */
 219 #define STATE_CMD_READ0        0x00000001 /* read data from the beginning of page */
 220 #define STATE_CMD_READ1        0x00000002 /* read data from the second half of page */
 221 #define STATE_CMD_READSTART    0x00000003 /* read data second command (large page devices) */
 222 #define STATE_CMD_PAGEPROG     0x00000004 /* start page program */
 223 #define STATE_CMD_READOOB      0x00000005 /* read OOB area */
 224 #define STATE_CMD_ERASE1       0x00000006 /* sector erase first command */
 225 #define STATE_CMD_STATUS       0x00000007 /* read status */
 226 #define STATE_CMD_SEQIN        0x00000009 /* sequential data input */
 227 #define STATE_CMD_READID       0x0000000A /* read ID */
 228 #define STATE_CMD_ERASE2       0x0000000B /* sector erase second command */
 229 #define STATE_CMD_RESET        0x0000000C /* reset */
 230 #define STATE_CMD_RNDOUT       0x0000000D /* random output command */
 231 #define STATE_CMD_RNDOUTSTART  0x0000000E /* random output start command */
 232 #define STATE_CMD_MASK         0x0000000F /* command states mask */
 233
 234 /* After an address is input, the simulator goes to one of these states */
 235 #define STATE_ADDR_PAGE        0x00000010 /* full (row, column) address is accepted */
 236 #define STATE_ADDR_SEC         0x00000020 /* sector address was accepted */
 237 #define STATE_ADDR_COLUMN      0x00000030 /* column address was accepted */
 238 #define STATE_ADDR_ZERO        0x00000040 /* one byte zero address was accepted */
 239 #define STATE_ADDR_MASK        0x00000070 /* address states mask */
 240
 241 /* During data input/output the simulator is in these states */
 242 #define STATE_DATAIN           0x00000100 /* waiting for data input */
 243 #define STATE_DATAIN_MASK      0x00000100 /* data input states mask */
 244
 245 #define STATE_DATAOUT          0x00001000 /* waiting for page data output */
 246 #define STATE_DATAOUT_ID       0x00002000 /* waiting for ID bytes output */
 247 #define STATE_DATAOUT_STATUS   0x00003000 /* waiting for status output */
 248 #define STATE_DATAOUT_MASK     0x00007000 /* data output states mask */
 249
 250 /* Previous operation is done, ready to accept new requests */
 251 #define STATE_READY            0x00000000
 252
 253 /* This state is used to mark that the next state isn't known yet */
 254 #define STATE_UNKNOWN          0x10000000
 255
 256 /* Simulator's actions bit masks */
 257 #define ACTION_CPY       0x00100000 /* copy page/OOB to the internal buffer */
 258 #define ACTION_PRGPAGE   0x00200000 /* program the internal buffer to flash */
 259 #define ACTION_SECERASE  0x00300000 /* erase sector */
 260 #define ACTION_ZEROOFF   0x00400000 /* don't add any offset to address */
 261 #define ACTION_HALFOFF   0x00500000 /* add to address half of page */
 262 #define ACTION_OOBOFF    0x00600000 /* add to address OOB offset */
 263 #define ACTION_MASK      0x00700000 /* action mask */
 264
 265 #define NS_OPER_NUM      13 /* Number of operations supported by the simulator */
 266 #define NS_OPER_STATES   6  /* Maximum number of states in operation */
 267
 268 #define OPT_ANY          0xFFFFFFFF /* any chip supports this operation */
 269 #define OPT_PAGE512      0x00000002 /* 512-byte  page chips */
 270 #define OPT_PAGE2048     0x00000008 /* 2048-byte page chips */
 271 #define OPT_PAGE512_8BIT 0x00000040 /* 512-byte page chips with 8-bit bus width */
 272 #define OPT_PAGE4096     0x00000080 /* 4096-byte page chips */
 273 #define OPT_LARGEPAGE    (OPT_PAGE2048 | OPT_PAGE4096) /* 2048 & 4096-byte page chips */
 274 #define OPT_SMALLPAGE    (OPT_PAGE512) /* 512-byte page chips */
 275
 276 /* Remove action bits from state */
 277 #define NS_STATE(x) ((x) & ~ACTION_MASK)
 278
 279 /*
 280  * Maximum previous states which need to be saved. Currently saving is
 281  * only needed for page program operation with preceded read command
 282  * (which is only valid for 512-byte pages).
 283  */
 284 #define NS_MAX_PREVSTATES 1
 285
 286 /* Maximum page cache pages needed to read or write a NAND page to the cache_file */
 287 #define NS_MAX_HELD_PAGES 16
 288
 289 /*
 290  * A union to represent flash memory contents and flash buffer.
 291  */
 292 union ns_mem {
 293         u_char *byte;    /* for byte access */
 294         uint16_t *word;  /* for 16-bit word access */
 295 };
 296
 297 /*
 298  * The structure which describes all the internal simulator data.
 299  */
 300 struct nandsim {
 301         struct nand_chip chip;
 302         struct nand_controller base;
 303         struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
 304         unsigned int nbparts;
 305
 306         uint busw;              /* flash chip bus width (8 or 16) */
 307         u_char ids[8];          /* chip's ID bytes */
 308         uint32_t options;       /* chip's characteristic bits */
 309         uint32_t state;         /* current chip state */
 310         uint32_t nxstate;       /* next expected state */
 311
 312         uint32_t *op;           /* current operation, NULL operations isn't known yet  */
 313         uint32_t pstates[NS_MAX_PREVSTATES]; /* previous states */
 314         uint16_t npstates;      /* number of previous states saved */
 315         uint16_t stateidx;      /* current state index */
 316
 317         /* The simulated NAND flash pages array */
 318         union ns_mem *pages;
 319
 320         /* Slab allocator for nand pages */
 321         struct kmem_cache *nand_pages_slab;
 322
 323         /* Internal buffer of page + OOB size bytes */
 324         union ns_mem buf;
 325
 326         /* NAND flash "geometry" */
 327         struct {
 328                 uint64_t totsz;     /* total flash size, bytes */
 329                 uint32_t secsz;     /* flash sector (erase block) size, bytes */
 330                 uint pgsz;          /* NAND flash page size, bytes */
 331                 uint oobsz;         /* page OOB area size, bytes */
 332                 uint64_t totszoob;  /* total flash size including OOB, bytes */
 333                 uint pgszoob;       /* page size including OOB , bytes*/
 334                 uint secszoob;      /* sector size including OOB, bytes */
 335                 uint pgnum;         /* total number of pages */
 336                 uint pgsec;         /* number of pages per sector */
 337                 uint secshift;      /* bits number in sector size */
 338                 uint pgshift;       /* bits number in page size */
 339                 uint pgaddrbytes;   /* bytes per page address */
 340                 uint secaddrbytes;  /* bytes per sector address */
 341                 uint idbytes;       /* the number ID bytes that this chip outputs */
 342         } geom;
 343
 344         /* NAND flash internal registers */
 345         struct {
 346                 unsigned command; /* the command register */
 347                 u_char   status;  /* the status register */
 348                 uint     row;     /* the page number */
 349                 uint     column;  /* the offset within page */
 350                 uint     count;   /* internal counter */
 351                 uint     num;     /* number of bytes which must be processed */
 352                 uint     off;     /* fixed page offset */
 353         } regs;
 354
 355         /* NAND flash lines state */
 356         struct {
 357                 int ce;  /* chip Enable */
 358                 int cle; /* command Latch Enable */
 359                 int ale; /* address Latch Enable */
 360                 int wp;  /* write Protect */
 361         } lines;
 362
 363         /* Fields needed when using a cache file */
 364         struct file *cfile; /* Open file */
 365         unsigned long *pages_written; /* Which pages have been written */
 366         void *file_buf;
 367         struct page *held_pages[NS_MAX_HELD_PAGES];
 368         int held_cnt;
 369 };
 370
 371 /*
 372  * Operations array. To perform any operation the simulator must pass
 373  * through the correspondent states chain.
 374  */
 375 static struct nandsim_operations {
 376         uint32_t reqopts;  /* options which are required to perform the operation */
 377         uint32_t states[NS_OPER_STATES]; /* operation's states */
 378 } ops[NS_OPER_NUM] = {
 379         /* Read page + OOB from the beginning */
 380         {OPT_SMALLPAGE, {STATE_CMD_READ0 | ACTION_ZEROOFF, STATE_ADDR_PAGE | ACTION_CPY,
 381                         STATE_DATAOUT, STATE_READY}},
 382         /* Read page + OOB from the second half */
 383         {OPT_PAGE512_8BIT, {STATE_CMD_READ1 | ACTION_HALFOFF, STATE_ADDR_PAGE | ACTION_CPY,
 384                         STATE_DATAOUT, STATE_READY}},
 385         /* Read OOB */
 386         {OPT_SMALLPAGE, {STATE_CMD_READOOB | ACTION_OOBOFF, STATE_ADDR_PAGE | ACTION_CPY,
 387                         STATE_DATAOUT, STATE_READY}},
 388         /* Program page starting from the beginning */
 389         {OPT_ANY, {STATE_CMD_SEQIN, STATE_ADDR_PAGE, STATE_DATAIN,
 390                         STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 391         /* Program page starting from the beginning */
 392         {OPT_SMALLPAGE, {STATE_CMD_READ0, STATE_CMD_SEQIN | ACTION_ZEROOFF, STATE_ADDR_PAGE,
 393                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 394         /* Program page starting from the second half */
 395         {OPT_PAGE512, {STATE_CMD_READ1, STATE_CMD_SEQIN | ACTION_HALFOFF, STATE_ADDR_PAGE,
 396                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 397         /* Program OOB */
 398         {OPT_SMALLPAGE, {STATE_CMD_READOOB, STATE_CMD_SEQIN | ACTION_OOBOFF, STATE_ADDR_PAGE,
 399                               STATE_DATAIN, STATE_CMD_PAGEPROG | ACTION_PRGPAGE, STATE_READY}},
 400         /* Erase sector */
 401         {OPT_ANY, {STATE_CMD_ERASE1, STATE_ADDR_SEC, STATE_CMD_ERASE2 | ACTION_SECERASE, STATE_READY}},
 402         /* Read status */
 403         {OPT_ANY, {STATE_CMD_STATUS, STATE_DATAOUT_STATUS, STATE_READY}},
 404         /* Read ID */
 405         {OPT_ANY, {STATE_CMD_READID, STATE_ADDR_ZERO, STATE_DATAOUT_ID, STATE_READY}},
 406         /* Large page devices read page */
 407         {OPT_LARGEPAGE, {STATE_CMD_READ0, STATE_ADDR_PAGE, STATE_CMD_READSTART | ACTION_CPY,
 408                                STATE_DATAOUT, STATE_READY}},
 409         /* Large page devices random page read */
 410         {OPT_LARGEPAGE, {STATE_CMD_RNDOUT, STATE_ADDR_COLUMN, STATE_CMD_RNDOUTSTART | ACTION_CPY,
 411                                STATE_DATAOUT, STATE_READY}},
 412 };
 413
 414 struct weak_block {
 415         struct list_head list;
 416         unsigned int erase_block_no;
 417         unsigned int max_erases;
 418         unsigned int erases_done;
 419 };
 420
 421 static LIST_HEAD(weak_blocks);
 422
 423 struct weak_page {
 424         struct list_head list;
 425         unsigned int page_no;
 426         unsigned int max_writes;
 427         unsigned int writes_done;
 428 };
 429
 430 static LIST_HEAD(weak_pages);
 431
 432 struct grave_page {
 433         struct list_head list;
 434         unsigned int page_no;
 435         unsigned int max_reads;
 436         unsigned int reads_done;
 437 };
 438
 439 static LIST_HEAD(grave_pages);
 440
 441 static unsigned long *erase_block_wear = NULL;
 442 static unsigned int wear_eb_count = 0;
 443 static unsigned long total_wear = 0;
 444
 445 /* MTD structure for NAND controller */
 446 static struct mtd_info *nsmtd;
 447
 448 static int nandsim_show(struct seq_file *m, void *private)
 449 {
 450         unsigned long wmin = -1, wmax = 0, avg;
 451         unsigned long deciles[10], decile_max[10], tot = 0;
 452         unsigned int i;
 453
 454         /* Calc wear stats */
 455         for (i = 0; i < wear_eb_count; ++i) {
 456                 unsigned long wear = erase_block_wear[i];
 457                 if (wear < wmin)
 458                         wmin = wear;
 459                 if (wear > wmax)
 460                         wmax = wear;
 461                 tot += wear;
 462         }
 463
 464         for (i = 0; i < 9; ++i) {
 465                 deciles[i] = 0;
 466                 decile_max[i] = (wmax * (i + 1) + 5) / 10;
 467         }
 468         deciles[9] = 0;
 469         decile_max[9] = wmax;
 470         for (i = 0; i < wear_eb_count; ++i) {
 471                 int d;
 472                 unsigned long wear = erase_block_wear[i];
 473                 for (d = 0; d < 10; ++d)
 474                         if (wear <= decile_max[d]) {
 475                                 deciles[d] += 1;
 476                                 break;
 477                         }
 478         }
 479         avg = tot / wear_eb_count;
 480
 481         /* Output wear report */
 482         seq_printf(m, "Total numbers of erases:  %lu\n", tot);
 483         seq_printf(m, "Number of erase blocks:   %u\n", wear_eb_count);
 484         seq_printf(m, "Average number of erases: %lu\n", avg);
 485         seq_printf(m, "Maximum number of erases: %lu\n", wmax);
 486         seq_printf(m, "Minimum number of erases: %lu\n", wmin);
 487         for (i = 0; i < 10; ++i) {
 488                 unsigned long from = (i ? decile_max[i - 1] + 1 : 0);
 489                 if (from > decile_max[i])
 490                         continue;
 491                 seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n",
 492                         from,
 493                         decile_max[i],
 494                         deciles[i]);
 495         }
 496
 497         return 0;
 498 }
 499 DEFINE_SHOW_ATTRIBUTE(nandsim);
 500
 501 /**
 502  * nandsim_debugfs_create - initialize debugfs
 503  * @dev: nandsim device description object
 504  *
 505  * This function creates all debugfs files for UBI device @ubi. Returns zero in
 506  * case of success and a negative error code in case of failure.
 507  */
 508 static int nandsim_debugfs_create(struct nandsim *dev)
 509 {
 510         struct dentry *root = nsmtd->dbg.dfs_dir;
 511         struct dentry *dent;
 512
 513         /*
 514          * Just skip debugfs initialization when the debugfs directory is
 515          * missing.
 516          */
 517         if (IS_ERR_OR_NULL(root)) {
 518                 if (IS_ENABLED(CONFIG_DEBUG_FS) &&
 519                     !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
 520                         NS_WARN("CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n");
 521                 return 0;
 522         }
 523
 524         dent = debugfs_create_file("nandsim_wear_report", S_IRUSR,
 525                                    root, dev, &nandsim_fops);
 526         if (IS_ERR_OR_NULL(dent)) {
 527                 NS_ERR("cannot create \"nandsim_wear_report\" debugfs entry\n");
 528                 return -1;
 529         }
 530
 531         return 0;
 532 }
 533
 534 /*
 535  * Allocate array of page pointers, create slab allocation for an array
 536  * and initialize the array by NULL pointers.
 537  *
 538  * RETURNS: 0 if success, -ENOMEM if memory alloc fails.
 539  */
 540 static int __init alloc_device(struct nandsim *ns)
 541 {
 542         struct file *cfile;
 543         int i, err;
 544
 545         if (cache_file) {
 546                 cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600);
 547                 if (IS_ERR(cfile))
 548                         return PTR_ERR(cfile);
 549                 if (!(cfile->f_mode & FMODE_CAN_READ)) {
 550                         NS_ERR("alloc_device: cache file not readable\n");
 551                         err = -EINVAL;
 552                         goto err_close;
 553                 }
 554                 if (!(cfile->f_mode & FMODE_CAN_WRITE)) {
 555                         NS_ERR("alloc_device: cache file not writeable\n");
 556                         err = -EINVAL;
 557                         goto err_close;
 558                 }
 559                 ns->pages_written =
 560                         vzalloc(array_size(sizeof(unsigned long),
 561                                            BITS_TO_LONGS(ns->geom.pgnum)));
 562                 if (!ns->pages_written) {
 563                         NS_ERR("alloc_device: unable to allocate pages written array\n");
 564                         err = -ENOMEM;
 565                         goto err_close;
 566                 }
 567                 ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 568                 if (!ns->file_buf) {
 569                         NS_ERR("alloc_device: unable to allocate file buf\n");
 570                         err = -ENOMEM;
 571                         goto err_free;
 572                 }
 573                 ns->cfile = cfile;
 574                 return 0;
 575         }
 576
 577         ns->pages = vmalloc(array_size(sizeof(union ns_mem), ns->geom.pgnum));
 578         if (!ns->pages) {
 579                 NS_ERR("alloc_device: unable to allocate page array\n");
 580                 return -ENOMEM;
 581         }
 582         for (i = 0; i < ns->geom.pgnum; i++) {
 583                 ns->pages[i].byte = NULL;
 584         }
 585         ns->nand_pages_slab = kmem_cache_create("nandsim",
 586                                                 ns->geom.pgszoob, 0, 0, NULL);
 587         if (!ns->nand_pages_slab) {
 588                 NS_ERR("cache_create: unable to create kmem_cache\n");
 589                 return -ENOMEM;
 590         }
 591
 592         return 0;
 593
 594 err_free:
 595         vfree(ns->pages_written);
 596 err_close:
 597         filp_close(cfile, NULL);
 598         return err;
 599 }
 600
 601 /*
 602  * Free any allocated pages, and free the array of page pointers.
 603  */
 604 static void free_device(struct nandsim *ns)
 605 {
 606         int i;
 607
 608         if (ns->cfile) {
 609                 kfree(ns->file_buf);
 610                 vfree(ns->pages_written);
 611                 filp_close(ns->cfile, NULL);
 612                 return;
 613         }
 614
 615         if (ns->pages) {
 616                 for (i = 0; i < ns->geom.pgnum; i++) {
 617                         if (ns->pages[i].byte)
 618                                 kmem_cache_free(ns->nand_pages_slab,
 619                                                 ns->pages[i].byte);
 620                 }
 621                 kmem_cache_destroy(ns->nand_pages_slab);
 622                 vfree(ns->pages);
 623         }
 624 }
 625
 626 static char __init *get_partition_name(int i)
 627 {
 628         return kasprintf(GFP_KERNEL, "NAND simulator partition %d", i);
 629 }
 630
 631 /*
 632  * Initialize the nandsim structure.
 633  *
 634  * RETURNS: 0 if success, -ERRNO if failure.
 635  */
 636 static int __init init_nandsim(struct mtd_info *mtd)
 637 {
 638         struct nand_chip *chip = mtd_to_nand(mtd);
 639         struct nandsim   *ns   = nand_get_controller_data(chip);
 640         int i, ret = 0;
 641         uint64_t remains;
 642         uint64_t next_offset;
 643
 644         if (NS_IS_INITIALIZED(ns)) {
 645                 NS_ERR("init_nandsim: nandsim is already initialized\n");
 646                 return -EIO;
 647         }
 648
 649         /* Initialize the NAND flash parameters */
 650         ns->busw = chip->options & NAND_BUSWIDTH_16 ? 16 : 8;
 651         ns->geom.totsz    = mtd->size;
 652         ns->geom.pgsz     = mtd->writesize;
 653         ns->geom.oobsz    = mtd->oobsize;
 654         ns->geom.secsz    = mtd->erasesize;
 655         ns->geom.pgszoob  = ns->geom.pgsz + ns->geom.oobsz;
 656         ns->geom.pgnum    = div_u64(ns->geom.totsz, ns->geom.pgsz);
 657         ns->geom.totszoob = ns->geom.totsz + (uint64_t)ns->geom.pgnum * ns->geom.oobsz;
 658         ns->geom.secshift = ffs(ns->geom.secsz) - 1;
 659         ns->geom.pgshift  = chip->page_shift;
 660         ns->geom.pgsec    = ns->geom.secsz / ns->geom.pgsz;
 661         ns->geom.secszoob = ns->geom.secsz + ns->geom.oobsz * ns->geom.pgsec;
 662         ns->options = 0;
 663
 664         if (ns->geom.pgsz == 512) {
 665                 ns->options |= OPT_PAGE512;
 666                 if (ns->busw == 8)
 667                         ns->options |= OPT_PAGE512_8BIT;
 668         } else if (ns->geom.pgsz == 2048) {
 669                 ns->options |= OPT_PAGE2048;
 670         } else if (ns->geom.pgsz == 4096) {
 671                 ns->options |= OPT_PAGE4096;
 672         } else {
 673                 NS_ERR("init_nandsim: unknown page size %u\n", ns->geom.pgsz);
 674                 return -EIO;
 675         }
 676
 677         if (ns->options & OPT_SMALLPAGE) {
 678                 if (ns->geom.totsz <= (32 << 20)) {
 679                         ns->geom.pgaddrbytes  = 3;
 680                         ns->geom.secaddrbytes = 2;
 681                 } else {
 682                         ns->geom.pgaddrbytes  = 4;
 683                         ns->geom.secaddrbytes = 3;
 684                 }
 685         } else {
 686                 if (ns->geom.totsz <= (128 << 20)) {
 687                         ns->geom.pgaddrbytes  = 4;
 688                         ns->geom.secaddrbytes = 2;
 689                 } else {
 690                         ns->geom.pgaddrbytes  = 5;
 691                         ns->geom.secaddrbytes = 3;
 692                 }
 693         }
 694
 695         /* Fill the partition_info structure */
 696         if (parts_num > ARRAY_SIZE(ns->partitions)) {
 697                 NS_ERR("too many partitions.\n");
 698                 return -EINVAL;
 699         }
 700         remains = ns->geom.totsz;
 701         next_offset = 0;
 702         for (i = 0; i < parts_num; ++i) {
 703                 uint64_t part_sz = (uint64_t)parts[i] * ns->geom.secsz;
 704
 705                 if (!part_sz || part_sz > remains) {
 706                         NS_ERR("bad partition size.\n");
 707                         return -EINVAL;
 708                 }
 709                 ns->partitions[i].name   = get_partition_name(i);
 710                 if (!ns->partitions[i].name) {
 711                         NS_ERR("unable to allocate memory.\n");
 712                         return -ENOMEM;
 713                 }
 714                 ns->partitions[i].offset = next_offset;
 715                 ns->partitions[i].size   = part_sz;
 716                 next_offset += ns->partitions[i].size;
 717                 remains -= ns->partitions[i].size;
 718         }
 719         ns->nbparts = parts_num;
 720         if (remains) {
 721                 if (parts_num + 1 > ARRAY_SIZE(ns->partitions)) {
 722                         NS_ERR("too many partitions.\n");
 723                         return -EINVAL;
 724                 }
 725                 ns->partitions[i].name   = get_partition_name(i);
 726                 if (!ns->partitions[i].name) {
 727                         NS_ERR("unable to allocate memory.\n");
 728                         return -ENOMEM;
 729                 }
 730                 ns->partitions[i].offset = next_offset;
 731                 ns->partitions[i].size   = remains;
 732                 ns->nbparts += 1;
 733         }
 734
 735         if (ns->busw == 16)
 736                 NS_WARN("16-bit flashes support wasn't tested\n");
 737
 738         printk("flash size: %llu MiB\n",
 739                         (unsigned long long)ns->geom.totsz >> 20);
 740         printk("page size: %u bytes\n",         ns->geom.pgsz);
 741         printk("OOB area size: %u bytes\n",     ns->geom.oobsz);
 742         printk("sector size: %u KiB\n",         ns->geom.secsz >> 10);
 743         printk("pages number: %u\n",            ns->geom.pgnum);
 744         printk("pages per sector: %u\n",        ns->geom.pgsec);
 745         printk("bus width: %u\n",               ns->busw);
 746         printk("bits in sector size: %u\n",     ns->geom.secshift);
 747         printk("bits in page size: %u\n",       ns->geom.pgshift);
 748         printk("bits in OOB size: %u\n",        ffs(ns->geom.oobsz) - 1);
 749         printk("flash size with OOB: %llu KiB\n",
 750                         (unsigned long long)ns->geom.totszoob >> 10);
 751         printk("page address bytes: %u\n",      ns->geom.pgaddrbytes);
 752         printk("sector address bytes: %u\n",    ns->geom.secaddrbytes);
 753         printk("options: %#x\n",                ns->options);
 754
 755         if ((ret = alloc_device(ns)) != 0)
 756                 return ret;
 757
 758         /* Allocate / initialize the internal buffer */
 759         ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
 760         if (!ns->buf.byte) {
 761                 NS_ERR("init_nandsim: unable to allocate %u bytes for the internal buffer\n",
 762                         ns->geom.pgszoob);
 763                 return -ENOMEM;
 764         }
 765         memset(ns->buf.byte, 0xFF, ns->geom.pgszoob);
 766
 767         return 0;
 768 }
 769
 770 /*
 771  * Free the nandsim structure.
 772  */
 773 static void free_nandsim(struct nandsim *ns)
 774 {
 775         kfree(ns->buf.byte);
 776         free_device(ns);
 777
 778         return;
 779 }
 780
 781 static int parse_badblocks(struct nandsim *ns, struct mtd_info *mtd)
 782 {
 783         char *w;
 784         int zero_ok;
 785         unsigned int erase_block_no;
 786         loff_t offset;
 787
 788         if (!badblocks)
 789                 return 0;
 790         w = badblocks;
 791         do {
 792                 zero_ok = (*w == '0' ? 1 : 0);
 793                 erase_block_no = simple_strtoul(w, &w, 0);
 794                 if (!zero_ok && !erase_block_no) {
 795                         NS_ERR("invalid badblocks.\n");
 796                         return -EINVAL;
 797                 }
 798                 offset = (loff_t)erase_block_no * ns->geom.secsz;
 799                 if (mtd_block_markbad(mtd, offset)) {
 800                         NS_ERR("invalid badblocks.\n");
 801                         return -EINVAL;
 802                 }
 803                 if (*w == ',')
 804                         w += 1;
 805         } while (*w);
 806         return 0;
 807 }
 808
 809 static int parse_weakblocks(void)
 810 {
 811         char *w;
 812         int zero_ok;
 813         unsigned int erase_block_no;
 814         unsigned int max_erases;
 815         struct weak_block *wb;
 816
 817         if (!weakblocks)
 818                 return 0;
 819         w = weakblocks;
 820         do {
 821                 zero_ok = (*w == '0' ? 1 : 0);
 822                 erase_block_no = simple_strtoul(w, &w, 0);
 823                 if (!zero_ok && !erase_block_no) {
 824                         NS_ERR("invalid weakblocks.\n");
 825                         return -EINVAL;
 826                 }
 827                 max_erases = 3;
 828                 if (*w == ':') {
 829                         w += 1;
 830                         max_erases = simple_strtoul(w, &w, 0);
 831                 }
 832                 if (*w == ',')
 833                         w += 1;
 834                 wb = kzalloc(sizeof(*wb), GFP_KERNEL);
 835                 if (!wb) {
 836                         NS_ERR("unable to allocate memory.\n");
 837                         return -ENOMEM;
 838                 }
 839                 wb->erase_block_no = erase_block_no;
 840                 wb->max_erases = max_erases;
 841                 list_add(&wb->list, &weak_blocks);
 842         } while (*w);
 843         return 0;
 844 }
 845
 846 static int erase_error(unsigned int erase_block_no)
 847 {
 848         struct weak_block *wb;
 849
 850         list_for_each_entry(wb, &weak_blocks, list)
 851                 if (wb->erase_block_no == erase_block_no) {
 852                         if (wb->erases_done >= wb->max_erases)
 853                                 return 1;
 854                         wb->erases_done += 1;
 855                         return 0;
 856                 }
 857         return 0;
 858 }
 859
 860 static int parse_weakpages(void)
 861 {
 862         char *w;
 863         int zero_ok;
 864         unsigned int page_no;
 865         unsigned int max_writes;
 866         struct weak_page *wp;
 867
 868         if (!weakpages)
 869                 return 0;
 870         w = weakpages;
 871         do {
 872                 zero_ok = (*w == '0' ? 1 : 0);
 873                 page_no = simple_strtoul(w, &w, 0);
 874                 if (!zero_ok && !page_no) {
 875                         NS_ERR("invalid weakpages.\n");
 876                         return -EINVAL;
 877                 }
 878                 max_writes = 3;
 879                 if (*w == ':') {
 880                         w += 1;
 881                         max_writes = simple_strtoul(w, &w, 0);
 882                 }
 883                 if (*w == ',')
 884                         w += 1;
 885                 wp = kzalloc(sizeof(*wp), GFP_KERNEL);
 886                 if (!wp) {
 887                         NS_ERR("unable to allocate memory.\n");
 888                         return -ENOMEM;
 889                 }
 890                 wp->page_no = page_no;
 891                 wp->max_writes = max_writes;
 892                 list_add(&wp->list, &weak_pages);
 893         } while (*w);
 894         return 0;
 895 }
 896
 897 static int write_error(unsigned int page_no)
 898 {
 899         struct weak_page *wp;
 900
 901         list_for_each_entry(wp, &weak_pages, list)
 902                 if (wp->page_no == page_no) {
 903                         if (wp->writes_done >= wp->max_writes)
 904                                 return 1;
 905                         wp->writes_done += 1;
 906                         return 0;
 907                 }
 908         return 0;
 909 }
 910
 911 static int parse_gravepages(void)
 912 {
 913         char *g;
 914         int zero_ok;
 915         unsigned int page_no;
 916         unsigned int max_reads;
 917         struct grave_page *gp;
 918
 919         if (!gravepages)
 920                 return 0;
 921         g = gravepages;
 922         do {
 923                 zero_ok = (*g == '0' ? 1 : 0);
 924                 page_no = simple_strtoul(g, &g, 0);
 925                 if (!zero_ok && !page_no) {
 926                         NS_ERR("invalid gravepagess.\n");
 927                         return -EINVAL;
 928                 }
 929                 max_reads = 3;
 930                 if (*g == ':') {
 931                         g += 1;
 932                         max_reads = simple_strtoul(g, &g, 0);
 933                 }
 934                 if (*g == ',')
 935                         g += 1;
 936                 gp = kzalloc(sizeof(*gp), GFP_KERNEL);
 937                 if (!gp) {
 938                         NS_ERR("unable to allocate memory.\n");
 939                         return -ENOMEM;
 940                 }
 941                 gp->page_no = page_no;
 942                 gp->max_reads = max_reads;
 943                 list_add(&gp->list, &grave_pages);
 944         } while (*g);
 945         return 0;
 946 }
 947
 948 static int read_error(unsigned int page_no)
 949 {
 950         struct grave_page *gp;
 951
 952         list_for_each_entry(gp, &grave_pages, list)
 953                 if (gp->page_no == page_no) {
 954                         if (gp->reads_done >= gp->max_reads)
 955                                 return 1;
 956                         gp->reads_done += 1;
 957                         return 0;
 958                 }
 959         return 0;
 960 }
 961
 962 static void free_lists(void)
 963 {
 964         struct list_head *pos, *n;
 965         list_for_each_safe(pos, n, &weak_blocks) {
 966                 list_del(pos);
 967                 kfree(list_entry(pos, struct weak_block, list));
 968         }
 969         list_for_each_safe(pos, n, &weak_pages) {
 970                 list_del(pos);
 971                 kfree(list_entry(pos, struct weak_page, list));
 972         }
 973         list_for_each_safe(pos, n, &grave_pages) {
 974                 list_del(pos);
 975                 kfree(list_entry(pos, struct grave_page, list));
 976         }
 977         kfree(erase_block_wear);
 978 }
 979
 980 static int setup_wear_reporting(struct mtd_info *mtd)
 981 {
 982         size_t mem;
 983
 984         wear_eb_count = div_u64(mtd->size, mtd->erasesize);
 985         mem = wear_eb_count * sizeof(unsigned long);
 986         if (mem / sizeof(unsigned long) != wear_eb_count) {
 987                 NS_ERR("Too many erase blocks for wear reporting\n");
 988                 return -ENOMEM;
 989         }
 990         erase_block_wear = kzalloc(mem, GFP_KERNEL);
 991         if (!erase_block_wear) {
 992                 NS_ERR("Too many erase blocks for wear reporting\n");
 993                 return -ENOMEM;
 994         }
 995         return 0;
 996 }
 997
 998 static void update_wear(unsigned int erase_block_no)
 999 {
1000         if (!erase_block_wear)
1001                 return;
1002         total_wear += 1;
1003         /*
1004          * TODO: Notify this through a debugfs entry,
1005          * instead of showing an error message.
1006          */
1007         if (total_wear == 0)
1008                 NS_ERR("Erase counter total overflow\n");
1009         erase_block_wear[erase_block_no] += 1;
1010         if (erase_block_wear[erase_block_no] == 0)
1011                 NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no);
1012 }
1013
1014 /*
1015  * Returns the string representation of 'state' state.
1016  */
1017 static char *get_state_name(uint32_t state)
1018 {
1019         switch (NS_STATE(state)) {
1020                 case STATE_CMD_READ0:
1021                         return "STATE_CMD_READ0";
1022                 case STATE_CMD_READ1:
1023                         return "STATE_CMD_READ1";
1024                 case STATE_CMD_PAGEPROG:
1025                         return "STATE_CMD_PAGEPROG";
1026                 case STATE_CMD_READOOB:
1027                         return "STATE_CMD_READOOB";
1028                 case STATE_CMD_READSTART:
1029                         return "STATE_CMD_READSTART";
1030                 case STATE_CMD_ERASE1:
1031                         return "STATE_CMD_ERASE1";
1032                 case STATE_CMD_STATUS:
1033                         return "STATE_CMD_STATUS";
1034                 case STATE_CMD_SEQIN:
1035                         return "STATE_CMD_SEQIN";
1036                 case STATE_CMD_READID:
1037                         return "STATE_CMD_READID";
1038                 case STATE_CMD_ERASE2:
1039                         return "STATE_CMD_ERASE2";
1040                 case STATE_CMD_RESET:
1041                         return "STATE_CMD_RESET";
1042                 case STATE_CMD_RNDOUT:
1043                         return "STATE_CMD_RNDOUT";
1044                 case STATE_CMD_RNDOUTSTART:
1045                         return "STATE_CMD_RNDOUTSTART";
1046                 case STATE_ADDR_PAGE:
1047                         return "STATE_ADDR_PAGE";
1048                 case STATE_ADDR_SEC:
1049                         return "STATE_ADDR_SEC";
1050                 case STATE_ADDR_ZERO:
1051                         return "STATE_ADDR_ZERO";
1052                 case STATE_ADDR_COLUMN:
1053                         return "STATE_ADDR_COLUMN";
1054                 case STATE_DATAIN:
1055                         return "STATE_DATAIN";
1056                 case STATE_DATAOUT:
1057                         return "STATE_DATAOUT";
1058                 case STATE_DATAOUT_ID:
1059                         return "STATE_DATAOUT_ID";
1060                 case STATE_DATAOUT_STATUS:
1061                         return "STATE_DATAOUT_STATUS";
1062                 case STATE_READY:
1063                         return "STATE_READY";
1064                 case STATE_UNKNOWN:
1065                         return "STATE_UNKNOWN";
1066         }
1067
1068         NS_ERR("get_state_name: unknown state, BUG\n");
1069         return NULL;
1070 }
1071
1072 /*
1073  * Check if command is valid.
1074  *
1075  * RETURNS: 1 if wrong command, 0 if right.
1076  */
1077 static int check_command(int cmd)
1078 {
1079         switch (cmd) {
1080
1081         case NAND_CMD_READ0:
1082         case NAND_CMD_READ1:
1083         case NAND_CMD_READSTART:
1084         case NAND_CMD_PAGEPROG:
1085         case NAND_CMD_READOOB:
1086         case NAND_CMD_ERASE1:
1087         case NAND_CMD_STATUS:
1088         case NAND_CMD_SEQIN:
1089         case NAND_CMD_READID:
1090         case NAND_CMD_ERASE2:
1091         case NAND_CMD_RESET:
1092         case NAND_CMD_RNDOUT:
1093         case NAND_CMD_RNDOUTSTART:
1094                 return 0;
1095
1096         default:
1097                 return 1;
1098         }
1099 }
1100
1101 /*
1102  * Returns state after command is accepted by command number.
1103  */
1104 static uint32_t get_state_by_command(unsigned command)
1105 {
1106         switch (command) {
1107                 case NAND_CMD_READ0:
1108                         return STATE_CMD_READ0;
1109                 case NAND_CMD_READ1:
1110                         return STATE_CMD_READ1;
1111                 case NAND_CMD_PAGEPROG:
1112                         return STATE_CMD_PAGEPROG;
1113                 case NAND_CMD_READSTART:
1114                         return STATE_CMD_READSTART;
1115                 case NAND_CMD_READOOB:
1116                         return STATE_CMD_READOOB;
1117                 case NAND_CMD_ERASE1:
1118                         return STATE_CMD_ERASE1;
1119                 case NAND_CMD_STATUS:
1120                         return STATE_CMD_STATUS;
1121                 case NAND_CMD_SEQIN:
1122                         return STATE_CMD_SEQIN;
1123                 case NAND_CMD_READID:
1124                         return STATE_CMD_READID;
1125                 case NAND_CMD_ERASE2:
1126                         return STATE_CMD_ERASE2;
1127                 case NAND_CMD_RESET:
1128                         return STATE_CMD_RESET;
1129                 case NAND_CMD_RNDOUT:
1130                         return STATE_CMD_RNDOUT;
1131                 case NAND_CMD_RNDOUTSTART:
1132                         return STATE_CMD_RNDOUTSTART;
1133         }
1134
1135         NS_ERR("get_state_by_command: unknown command, BUG\n");
1136         return 0;
1137 }
1138
1139 /*
1140  * Move an address byte to the correspondent internal register.
1141  */
1142 static inline void accept_addr_byte(struct nandsim *ns, u_char bt)
1143 {
1144         uint byte = (uint)bt;
1145
1146         if (ns->regs.count < (ns->geom.pgaddrbytes - ns->geom.secaddrbytes))
1147                 ns->regs.column |= (byte << 8 * ns->regs.count);
1148         else {
1149                 ns->regs.row |= (byte << 8 * (ns->regs.count -
1150                                                 ns->geom.pgaddrbytes +
1151                                                 ns->geom.secaddrbytes));
1152         }
1153
1154         return;
1155 }
1156
1157 /*
1158  * Switch to STATE_READY state.
1159  */
1160 static inline void switch_to_ready_state(struct nandsim *ns, u_char status)
1161 {
1162         NS_DBG("switch_to_ready_state: switch to %s state\n", get_state_name(STATE_READY));
1163
1164         ns->state       = STATE_READY;
1165         ns->nxstate     = STATE_UNKNOWN;
1166         ns->op          = NULL;
1167         ns->npstates    = 0;
1168         ns->stateidx    = 0;
1169         ns->regs.num    = 0;
1170         ns->regs.count  = 0;
1171         ns->regs.off    = 0;
1172         ns->regs.row    = 0;
1173         ns->regs.column = 0;
1174         ns->regs.status = status;
1175 }
1176
1177 /*
1178  * If the operation isn't known yet, try to find it in the global array
1179  * of supported operations.
1180  *
1181  * Operation can be unknown because of the following.
1182  *   1. New command was accepted and this is the first call to find the
1183  *      correspondent states chain. In this case ns->npstates = 0;
1184  *   2. There are several operations which begin with the same command(s)
1185  *      (for example program from the second half and read from the
1186  *      second half operations both begin with the READ1 command). In this
1187  *      case the ns->pstates[] array contains previous states.
1188  *
1189  * Thus, the function tries to find operation containing the following
1190  * states (if the 'flag' parameter is 0):
1191  *    ns->pstates[0], ... ns->pstates[ns->npstates], ns->state
1192  *
1193  * If (one and only one) matching operation is found, it is accepted (
1194  * ns->ops, ns->state, ns->nxstate are initialized, ns->npstate is
1195  * zeroed).
1196  *
1197  * If there are several matches, the current state is pushed to the
1198  * ns->pstates.
1199  *
1200  * The operation can be unknown only while commands are input to the chip.
1201  * As soon as address command is accepted, the operation must be known.
1202  * In such situation the function is called with 'flag' != 0, and the
1203  * operation is searched using the following pattern:
1204  *     ns->pstates[0], ... ns->pstates[ns->npstates], <address input>
1205  *
1206  * It is supposed that this pattern must either match one operation or
1207  * none. There can't be ambiguity in that case.
1208  *
1209  * If no matches found, the function does the following:
1210  *   1. if there are saved states present, try to ignore them and search
1211  *      again only using the last command. If nothing was found, switch
1212  *      to the STATE_READY state.
1213  *   2. if there are no saved states, switch to the STATE_READY state.
1214  *
1215  * RETURNS: -2 - no matched operations found.
1216  *          -1 - several matches.
1217  *           0 - operation is found.
1218  */
1219 static int find_operation(struct nandsim *ns, uint32_t flag)
1220 {
1221         int opsfound = 0;
1222         int i, j, idx = 0;
1223
1224         for (i = 0; i < NS_OPER_NUM; i++) {
1225
1226                 int found = 1;
1227
1228                 if (!(ns->options & ops[i].reqopts))
1229                         /* Ignore operations we can't perform */
1230                         continue;
1231
1232                 if (flag) {
1233                         if (!(ops[i].states[ns->npstates] & STATE_ADDR_MASK))
1234                                 continue;
1235                 } else {
1236                         if (NS_STATE(ns->state) != NS_STATE(ops[i].states[ns->npstates]))
1237                                 continue;
1238                 }
1239
1240                 for (j = 0; j < ns->npstates; j++)
1241                         if (NS_STATE(ops[i].states[j]) != NS_STATE(ns->pstates[j])
1242                                 && (ns->options & ops[idx].reqopts)) {
1243                                 found = 0;
1244                                 break;
1245                         }
1246
1247                 if (found) {
1248                         idx = i;
1249                         opsfound += 1;
1250                 }
1251         }
1252
1253         if (opsfound == 1) {
1254                 /* Exact match */
1255                 ns->op = &ops[idx].states[0];
1256                 if (flag) {
1257                         /*
1258                          * In this case the find_operation function was
1259                          * called when address has just began input. But it isn't
1260                          * yet fully input and the current state must
1261                          * not be one of STATE_ADDR_*, but the STATE_ADDR_*
1262                          * state must be the next state (ns->nxstate).
1263                          */
1264                         ns->stateidx = ns->npstates - 1;
1265                 } else {
1266                         ns->stateidx = ns->npstates;
1267                 }
1268                 ns->npstates = 0;
1269                 ns->state = ns->op[ns->stateidx];
1270                 ns->nxstate = ns->op[ns->stateidx + 1];
1271                 NS_DBG("find_operation: operation found, index: %d, state: %s, nxstate %s\n",
1272                                 idx, get_state_name(ns->state), get_state_name(ns->nxstate));
1273                 return 0;
1274         }
1275
1276         if (opsfound == 0) {
1277                 /* Nothing was found. Try to ignore previous commands (if any) and search again */
1278                 if (ns->npstates != 0) {
1279                         NS_DBG("find_operation: no operation found, try again with state %s\n",
1280                                         get_state_name(ns->state));
1281                         ns->npstates = 0;
1282                         return find_operation(ns, 0);
1283
1284                 }
1285                 NS_DBG("find_operation: no operations found\n");
1286                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1287                 return -2;
1288         }
1289
1290         if (flag) {
1291                 /* This shouldn't happen */
1292                 NS_DBG("find_operation: BUG, operation must be known if address is input\n");
1293                 return -2;
1294         }
1295
1296         NS_DBG("find_operation: there is still ambiguity\n");
1297
1298         ns->pstates[ns->npstates++] = ns->state;
1299
1300         return -1;
1301 }
1302
1303 static void put_pages(struct nandsim *ns)
1304 {
1305         int i;
1306
1307         for (i = 0; i < ns->held_cnt; i++)
1308                 put_page(ns->held_pages[i]);
1309 }
1310
1311 /* Get page cache pages in advance to provide NOFS memory allocation */
1312 static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos)
1313 {
1314         pgoff_t index, start_index, end_index;
1315         struct page *page;
1316         struct address_space *mapping = file->f_mapping;
1317
1318         start_index = pos >> PAGE_SHIFT;
1319         end_index = (pos + count - 1) >> PAGE_SHIFT;
1320         if (end_index - start_index + 1 > NS_MAX_HELD_PAGES)
1321                 return -EINVAL;
1322         ns->held_cnt = 0;
1323         for (index = start_index; index <= end_index; index++) {
1324                 page = find_get_page(mapping, index);
1325                 if (page == NULL) {
1326                         page = find_or_create_page(mapping, index, GFP_NOFS);
1327                         if (page == NULL) {
1328                                 write_inode_now(mapping->host, 1);
1329                                 page = find_or_create_page(mapping, index, GFP_NOFS);
1330                         }
1331                         if (page == NULL) {
1332                                 put_pages(ns);
1333                                 return -ENOMEM;
1334                         }
1335                         unlock_page(page);
1336                 }
1337                 ns->held_pages[ns->held_cnt++] = page;
1338         }
1339         return 0;
1340 }
1341
1342 static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1343 {
1344         ssize_t tx;
1345         int err;
1346         unsigned int noreclaim_flag;
1347
1348         err = get_pages(ns, file, count, pos);
1349         if (err)
1350                 return err;
1351         noreclaim_flag = memalloc_noreclaim_save();
1352         tx = kernel_read(file, buf, count, &pos);
1353         memalloc_noreclaim_restore(noreclaim_flag);
1354         put_pages(ns);
1355         return tx;
1356 }
1357
1358 static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t pos)
1359 {
1360         ssize_t tx;
1361         int err;
1362         unsigned int noreclaim_flag;
1363
1364         err = get_pages(ns, file, count, pos);
1365         if (err)
1366                 return err;
1367         noreclaim_flag = memalloc_noreclaim_save();
1368         tx = kernel_write(file, buf, count, &pos);
1369         memalloc_noreclaim_restore(noreclaim_flag);
1370         put_pages(ns);
1371         return tx;
1372 }
1373
1374 /*
1375  * Returns a pointer to the current page.
1376  */
1377 static inline union ns_mem *NS_GET_PAGE(struct nandsim *ns)
1378 {
1379         return &(ns->pages[ns->regs.row]);
1380 }
1381
1382 /*
1383  * Retuns a pointer to the current byte, within the current page.
1384  */
1385 static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
1386 {
1387         return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
1388 }
1389
1390 static int do_read_error(struct nandsim *ns, int num)
1391 {
1392         unsigned int page_no = ns->regs.row;
1393
1394         if (read_error(page_no)) {
1395                 prandom_bytes(ns->buf.byte, num);
1396                 NS_WARN("simulating read error in page %u\n", page_no);
1397                 return 1;
1398         }
1399         return 0;
1400 }
1401
1402 static void do_bit_flips(struct nandsim *ns, int num)
1403 {
1404         if (bitflips && prandom_u32() < (1 << 22)) {
1405                 int flips = 1;
1406                 if (bitflips > 1)
1407                         flips = (prandom_u32() % (int) bitflips) + 1;
1408                 while (flips--) {
1409                         int pos = prandom_u32() % (num * 8);
1410                         ns->buf.byte[pos / 8] ^= (1 << (pos % 8));
1411                         NS_WARN("read_page: flipping bit %d in page %d "
1412                                 "reading from %d ecc: corrected=%u failed=%u\n",
1413                                 pos, ns->regs.row, ns->regs.column + ns->regs.off,
1414                                 nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed);
1415                 }
1416         }
1417 }
1418
1419 /*
1420  * Fill the NAND buffer with data read from the specified page.
1421  */
1422 static void read_page(struct nandsim *ns, int num)
1423 {
1424         union ns_mem *mypage;
1425
1426         if (ns->cfile) {
1427                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1428                         NS_DBG("read_page: page %d not written\n", ns->regs.row);
1429                         memset(ns->buf.byte, 0xFF, num);
1430                 } else {
1431                         loff_t pos;
1432                         ssize_t tx;
1433
1434                         NS_DBG("read_page: page %d written, reading from %d\n",
1435                                 ns->regs.row, ns->regs.column + ns->regs.off);
1436                         if (do_read_error(ns, num))
1437                                 return;
1438                         pos = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1439                         tx = read_file(ns, ns->cfile, ns->buf.byte, num, pos);
1440                         if (tx != num) {
1441                                 NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1442                                 return;
1443                         }
1444                         do_bit_flips(ns, num);
1445                 }
1446                 return;
1447         }
1448
1449         mypage = NS_GET_PAGE(ns);
1450         if (mypage->byte == NULL) {
1451                 NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
1452                 memset(ns->buf.byte, 0xFF, num);
1453         } else {
1454                 NS_DBG("read_page: page %d allocated, reading from %d\n",
1455                         ns->regs.row, ns->regs.column + ns->regs.off);
1456                 if (do_read_error(ns, num))
1457                         return;
1458                 memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
1459                 do_bit_flips(ns, num);
1460         }
1461 }
1462
1463 /*
1464  * Erase all pages in the specified sector.
1465  */
1466 static void erase_sector(struct nandsim *ns)
1467 {
1468         union ns_mem *mypage;
1469         int i;
1470
1471         if (ns->cfile) {
1472                 for (i = 0; i < ns->geom.pgsec; i++)
1473                         if (__test_and_clear_bit(ns->regs.row + i,
1474                                                  ns->pages_written)) {
1475                                 NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i);
1476                         }
1477                 return;
1478         }
1479
1480         mypage = NS_GET_PAGE(ns);
1481         for (i = 0; i < ns->geom.pgsec; i++) {
1482                 if (mypage->byte != NULL) {
1483                         NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
1484                         kmem_cache_free(ns->nand_pages_slab, mypage->byte);
1485                         mypage->byte = NULL;
1486                 }
1487                 mypage++;
1488         }
1489 }
1490
1491 /*
1492  * Program the specified page with the contents from the NAND buffer.
1493  */
1494 static int prog_page(struct nandsim *ns, int num)
1495 {
1496         int i;
1497         union ns_mem *mypage;
1498         u_char *pg_off;
1499
1500         if (ns->cfile) {
1501                 loff_t off;
1502                 ssize_t tx;
1503                 int all;
1504
1505                 NS_DBG("prog_page: writing page %d\n", ns->regs.row);
1506                 pg_off = ns->file_buf + ns->regs.column + ns->regs.off;
1507                 off = (loff_t)NS_RAW_OFFSET(ns) + ns->regs.off;
1508                 if (!test_bit(ns->regs.row, ns->pages_written)) {
1509                         all = 1;
1510                         memset(ns->file_buf, 0xff, ns->geom.pgszoob);
1511                 } else {
1512                         all = 0;
1513                         tx = read_file(ns, ns->cfile, pg_off, num, off);
1514                         if (tx != num) {
1515                                 NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx);
1516                                 return -1;
1517                         }
1518                 }
1519                 for (i = 0; i < num; i++)
1520                         pg_off[i] &= ns->buf.byte[i];
1521                 if (all) {
1522                         loff_t pos = (loff_t)ns->regs.row * ns->geom.pgszoob;
1523                         tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, pos);
1524                         if (tx != ns->geom.pgszoob) {
1525                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1526                                 return -1;
1527                         }
1528                         __set_bit(ns->regs.row, ns->pages_written);
1529                 } else {
1530                         tx = write_file(ns, ns->cfile, pg_off, num, off);
1531                         if (tx != num) {
1532                                 NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx);
1533                                 return -1;
1534                         }
1535                 }
1536                 return 0;
1537         }
1538
1539         mypage = NS_GET_PAGE(ns);
1540         if (mypage->byte == NULL) {
1541                 NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
1542                 /*
1543                  * We allocate memory with GFP_NOFS because a flash FS may
1544                  * utilize this. If it is holding an FS lock, then gets here,
1545                  * then kernel memory alloc runs writeback which goes to the FS
1546                  * again and deadlocks. This was seen in practice.
1547                  */
1548                 mypage->byte = kmem_cache_alloc(ns->nand_pages_slab, GFP_NOFS);
1549                 if (mypage->byte == NULL) {
1550                         NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
1551                         return -1;
1552                 }
1553                 memset(mypage->byte, 0xFF, ns->geom.pgszoob);
1554         }
1555
1556         pg_off = NS_PAGE_BYTE_OFF(ns);
1557         for (i = 0; i < num; i++)
1558                 pg_off[i] &= ns->buf.byte[i];
1559
1560         return 0;
1561 }
1562
1563 /*
1564  * If state has any action bit, perform this action.
1565  *
1566  * RETURNS: 0 if success, -1 if error.
1567  */
1568 static int do_state_action(struct nandsim *ns, uint32_t action)
1569 {
1570         int num;
1571         int busdiv = ns->busw == 8 ? 1 : 2;
1572         unsigned int erase_block_no, page_no;
1573
1574         action &= ACTION_MASK;
1575
1576         /* Check that page address input is correct */
1577         if (action != ACTION_SECERASE && ns->regs.row >= ns->geom.pgnum) {
1578                 NS_WARN("do_state_action: wrong page number (%#x)\n", ns->regs.row);
1579                 return -1;
1580         }
1581
1582         switch (action) {
1583
1584         case ACTION_CPY:
1585                 /*
1586                  * Copy page data to the internal buffer.
1587                  */
1588
1589                 /* Column shouldn't be very large */
1590                 if (ns->regs.column >= (ns->geom.pgszoob - ns->regs.off)) {
1591                         NS_ERR("do_state_action: column number is too large\n");
1592                         break;
1593                 }
1594                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1595                 read_page(ns, num);
1596
1597                 NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
1598                         num, NS_RAW_OFFSET(ns) + ns->regs.off);
1599
1600                 if (ns->regs.off == 0)
1601                         NS_LOG("read page %d\n", ns->regs.row);
1602                 else if (ns->regs.off < ns->geom.pgsz)
1603                         NS_LOG("read page %d (second half)\n", ns->regs.row);
1604                 else
1605                         NS_LOG("read OOB of page %d\n", ns->regs.row);
1606
1607                 NS_UDELAY(access_delay);
1608                 NS_UDELAY(input_cycle * ns->geom.pgsz / 1000 / busdiv);
1609
1610                 break;
1611
1612         case ACTION_SECERASE:
1613                 /*
1614                  * Erase sector.
1615                  */
1616
1617                 if (ns->lines.wp) {
1618                         NS_ERR("do_state_action: device is write-protected, ignore sector erase\n");
1619                         return -1;
1620                 }
1621
1622                 if (ns->regs.row >= ns->geom.pgnum - ns->geom.pgsec
1623                         || (ns->regs.row & ~(ns->geom.secsz - 1))) {
1624                         NS_ERR("do_state_action: wrong sector address (%#x)\n", ns->regs.row);
1625                         return -1;
1626                 }
1627
1628                 ns->regs.row = (ns->regs.row <<
1629                                 8 * (ns->geom.pgaddrbytes - ns->geom.secaddrbytes)) | ns->regs.column;
1630                 ns->regs.column = 0;
1631
1632                 erase_block_no = ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift);
1633
1634                 NS_DBG("do_state_action: erase sector at address %#x, off = %d\n",
1635                                 ns->regs.row, NS_RAW_OFFSET(ns));
1636                 NS_LOG("erase sector %u\n", erase_block_no);
1637
1638                 erase_sector(ns);
1639
1640                 NS_MDELAY(erase_delay);
1641
1642                 if (erase_block_wear)
1643                         update_wear(erase_block_no);
1644
1645                 if (erase_error(erase_block_no)) {
1646                         NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
1647                         return -1;
1648                 }
1649
1650                 break;
1651
1652         case ACTION_PRGPAGE:
1653                 /*
1654                  * Program page - move internal buffer data to the page.
1655                  */
1656
1657                 if (ns->lines.wp) {
1658                         NS_WARN("do_state_action: device is write-protected, programm\n");
1659                         return -1;
1660                 }
1661
1662                 num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1663                 if (num != ns->regs.count) {
1664                         NS_ERR("do_state_action: too few bytes were input (%d instead of %d)\n",
1665                                         ns->regs.count, num);
1666                         return -1;
1667                 }
1668
1669                 if (prog_page(ns, num) == -1)
1670                         return -1;
1671
1672                 page_no = ns->regs.row;
1673
1674                 NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
1675                         num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
1676                 NS_LOG("programm page %d\n", ns->regs.row);
1677
1678                 NS_UDELAY(programm_delay);
1679                 NS_UDELAY(output_cycle * ns->geom.pgsz / 1000 / busdiv);
1680
1681                 if (write_error(page_no)) {
1682                         NS_WARN("simulating write failure in page %u\n", page_no);
1683                         return -1;
1684                 }
1685
1686                 break;
1687
1688         case ACTION_ZEROOFF:
1689                 NS_DBG("do_state_action: set internal offset to 0\n");
1690                 ns->regs.off = 0;
1691                 break;
1692
1693         case ACTION_HALFOFF:
1694                 if (!(ns->options & OPT_PAGE512_8BIT)) {
1695                         NS_ERR("do_state_action: BUG! can't skip half of page for non-512"
1696                                 "byte page size 8x chips\n");
1697                         return -1;
1698                 }
1699                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz/2);
1700                 ns->regs.off = ns->geom.pgsz/2;
1701                 break;
1702
1703         case ACTION_OOBOFF:
1704                 NS_DBG("do_state_action: set internal offset to %d\n", ns->geom.pgsz);
1705                 ns->regs.off = ns->geom.pgsz;
1706                 break;
1707
1708         default:
1709                 NS_DBG("do_state_action: BUG! unknown action\n");
1710         }
1711
1712         return 0;
1713 }
1714
1715 /*
1716  * Switch simulator's state.
1717  */
1718 static void switch_state(struct nandsim *ns)
1719 {
1720         if (ns->op) {
1721                 /*
1722                  * The current operation have already been identified.
1723                  * Just follow the states chain.
1724                  */
1725
1726                 ns->stateidx += 1;
1727                 ns->state = ns->nxstate;
1728                 ns->nxstate = ns->op[ns->stateidx + 1];
1729
1730                 NS_DBG("switch_state: operation is known, switch to the next state, "
1731                         "state: %s, nxstate: %s\n",
1732                         get_state_name(ns->state), get_state_name(ns->nxstate));
1733
1734                 /* See, whether we need to do some action */
1735                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1736                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1737                         return;
1738                 }
1739
1740         } else {
1741                 /*
1742                  * We don't yet know which operation we perform.
1743                  * Try to identify it.
1744                  */
1745
1746                 /*
1747                  *  The only event causing the switch_state function to
1748                  *  be called with yet unknown operation is new command.
1749                  */
1750                 ns->state = get_state_by_command(ns->regs.command);
1751
1752                 NS_DBG("switch_state: operation is unknown, try to find it\n");
1753
1754                 if (find_operation(ns, 0) != 0)
1755                         return;
1756
1757                 if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1758                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1759                         return;
1760                 }
1761         }
1762
1763         /* For 16x devices column means the page offset in words */
1764         if ((ns->nxstate & STATE_ADDR_MASK) && ns->busw == 16) {
1765                 NS_DBG("switch_state: double the column number for 16x device\n");
1766                 ns->regs.column <<= 1;
1767         }
1768
1769         if (NS_STATE(ns->nxstate) == STATE_READY) {
1770                 /*
1771                  * The current state is the last. Return to STATE_READY
1772                  */
1773
1774                 u_char status = NS_STATUS_OK(ns);
1775
1776                 /* In case of data states, see if all bytes were input/output */
1777                 if ((ns->state & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK))
1778                         && ns->regs.count != ns->regs.num) {
1779                         NS_WARN("switch_state: not all bytes were processed, %d left\n",
1780                                         ns->regs.num - ns->regs.count);
1781                         status = NS_STATUS_FAILED(ns);
1782                 }
1783
1784                 NS_DBG("switch_state: operation complete, switch to STATE_READY state\n");
1785
1786                 switch_to_ready_state(ns, status);
1787
1788                 return;
1789         } else if (ns->nxstate & (STATE_DATAIN_MASK | STATE_DATAOUT_MASK)) {
1790                 /*
1791                  * If the next state is data input/output, switch to it now
1792                  */
1793
1794                 ns->state      = ns->nxstate;
1795                 ns->nxstate    = ns->op[++ns->stateidx + 1];
1796                 ns->regs.num   = ns->regs.count = 0;
1797
1798                 NS_DBG("switch_state: the next state is data I/O, switch, "
1799                         "state: %s, nxstate: %s\n",
1800                         get_state_name(ns->state), get_state_name(ns->nxstate));
1801
1802                 /*
1803                  * Set the internal register to the count of bytes which
1804                  * are expected to be input or output
1805                  */
1806                 switch (NS_STATE(ns->state)) {
1807                         case STATE_DATAIN:
1808                         case STATE_DATAOUT:
1809                                 ns->regs.num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
1810                                 break;
1811
1812                         case STATE_DATAOUT_ID:
1813                                 ns->regs.num = ns->geom.idbytes;
1814                                 break;
1815
1816                         case STATE_DATAOUT_STATUS:
1817                                 ns->regs.count = ns->regs.num = 0;
1818                                 break;
1819
1820                         default:
1821                                 NS_ERR("switch_state: BUG! unknown data state\n");
1822                 }
1823
1824         } else if (ns->nxstate & STATE_ADDR_MASK) {
1825                 /*
1826                  * If the next state is address input, set the internal
1827                  * register to the number of expected address bytes
1828                  */
1829
1830                 ns->regs.count = 0;
1831
1832                 switch (NS_STATE(ns->nxstate)) {
1833                         case STATE_ADDR_PAGE:
1834                                 ns->regs.num = ns->geom.pgaddrbytes;
1835
1836                                 break;
1837                         case STATE_ADDR_SEC:
1838                                 ns->regs.num = ns->geom.secaddrbytes;
1839                                 break;
1840
1841                         case STATE_ADDR_ZERO:
1842                                 ns->regs.num = 1;
1843                                 break;
1844
1845                         case STATE_ADDR_COLUMN:
1846                                 /* Column address is always 2 bytes */
1847                                 ns->regs.num = ns->geom.pgaddrbytes - ns->geom.secaddrbytes;
1848                                 break;
1849
1850                         default:
1851                                 NS_ERR("switch_state: BUG! unknown address state\n");
1852                 }
1853         } else {
1854                 /*
1855                  * Just reset internal counters.
1856                  */
1857
1858                 ns->regs.num = 0;
1859                 ns->regs.count = 0;
1860         }
1861 }
1862
1863 static u_char ns_nand_read_byte(struct nand_chip *chip)
1864 {
1865         struct nandsim *ns = nand_get_controller_data(chip);
1866         u_char outb = 0x00;
1867
1868         /* Sanity and correctness checks */
1869         if (!ns->lines.ce) {
1870                 NS_ERR("read_byte: chip is disabled, return %#x\n", (uint)outb);
1871                 return outb;
1872         }
1873         if (ns->lines.ale || ns->lines.cle) {
1874                 NS_ERR("read_byte: ALE or CLE pin is high, return %#x\n", (uint)outb);
1875                 return outb;
1876         }
1877         if (!(ns->state & STATE_DATAOUT_MASK)) {
1878                 NS_WARN("read_byte: unexpected data output cycle, state is %s "
1879                         "return %#x\n", get_state_name(ns->state), (uint)outb);
1880                 return outb;
1881         }
1882
1883         /* Status register may be read as many times as it is wanted */
1884         if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS) {
1885                 NS_DBG("read_byte: return %#x status\n", ns->regs.status);
1886                 return ns->regs.status;
1887         }
1888
1889         /* Check if there is any data in the internal buffer which may be read */
1890         if (ns->regs.count == ns->regs.num) {
1891                 NS_WARN("read_byte: no more data to output, return %#x\n", (uint)outb);
1892                 return outb;
1893         }
1894
1895         switch (NS_STATE(ns->state)) {
1896                 case STATE_DATAOUT:
1897                         if (ns->busw == 8) {
1898                                 outb = ns->buf.byte[ns->regs.count];
1899                                 ns->regs.count += 1;
1900                         } else {
1901                                 outb = (u_char)cpu_to_le16(ns->buf.word[ns->regs.count >> 1]);
1902                                 ns->regs.count += 2;
1903                         }
1904                         break;
1905                 case STATE_DATAOUT_ID:
1906                         NS_DBG("read_byte: read ID byte %d, total = %d\n", ns->regs.count, ns->regs.num);
1907                         outb = ns->ids[ns->regs.count];
1908                         ns->regs.count += 1;
1909                         break;
1910                 default:
1911                         BUG();
1912         }
1913
1914         if (ns->regs.count == ns->regs.num) {
1915                 NS_DBG("read_byte: all bytes were read\n");
1916
1917                 if (NS_STATE(ns->nxstate) == STATE_READY)
1918                         switch_state(ns);
1919         }
1920
1921         return outb;
1922 }
1923
1924 static void ns_nand_write_byte(struct nand_chip *chip, u_char byte)
1925 {
1926         struct nandsim *ns = nand_get_controller_data(chip);
1927
1928         /* Sanity and correctness checks */
1929         if (!ns->lines.ce) {
1930                 NS_ERR("write_byte: chip is disabled, ignore write\n");
1931                 return;
1932         }
1933         if (ns->lines.ale && ns->lines.cle) {
1934                 NS_ERR("write_byte: ALE and CLE pins are high simultaneously, ignore write\n");
1935                 return;
1936         }
1937
1938         if (ns->lines.cle == 1) {
1939                 /*
1940                  * The byte written is a command.
1941                  */
1942
1943                 if (byte == NAND_CMD_RESET) {
1944                         NS_LOG("reset chip\n");
1945                         switch_to_ready_state(ns, NS_STATUS_OK(ns));
1946                         return;
1947                 }
1948
1949                 /* Check that the command byte is correct */
1950                 if (check_command(byte)) {
1951                         NS_ERR("write_byte: unknown command %#x\n", (uint)byte);
1952                         return;
1953                 }
1954
1955                 if (NS_STATE(ns->state) == STATE_DATAOUT_STATUS
1956                         || NS_STATE(ns->state) == STATE_DATAOUT) {
1957                         int row = ns->regs.row;
1958
1959                         switch_state(ns);
1960                         if (byte == NAND_CMD_RNDOUT)
1961                                 ns->regs.row = row;
1962                 }
1963
1964                 /* Check if chip is expecting command */
1965                 if (NS_STATE(ns->nxstate) != STATE_UNKNOWN && !(ns->nxstate & STATE_CMD_MASK)) {
1966                         /* Do not warn if only 2 id bytes are read */
1967                         if (!(ns->regs.command == NAND_CMD_READID &&
1968                             NS_STATE(ns->state) == STATE_DATAOUT_ID && ns->regs.count == 2)) {
1969                                 /*
1970                                  * We are in situation when something else (not command)
1971                                  * was expected but command was input. In this case ignore
1972                                  * previous command(s)/state(s) and accept the last one.
1973                                  */
1974                                 NS_WARN("write_byte: command (%#x) wasn't expected, expected state is %s, "
1975                                         "ignore previous states\n", (uint)byte, get_state_name(ns->nxstate));
1976                         }
1977                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1978                 }
1979
1980                 NS_DBG("command byte corresponding to %s state accepted\n",
1981                         get_state_name(get_state_by_command(byte)));
1982                 ns->regs.command = byte;
1983                 switch_state(ns);
1984
1985         } else if (ns->lines.ale == 1) {
1986                 /*
1987                  * The byte written is an address.
1988                  */
1989
1990                 if (NS_STATE(ns->nxstate) == STATE_UNKNOWN) {
1991
1992                         NS_DBG("write_byte: operation isn't known yet, identify it\n");
1993
1994                         if (find_operation(ns, 1) < 0)
1995                                 return;
1996
1997                         if ((ns->state & ACTION_MASK) && do_state_action(ns, ns->state) < 0) {
1998                                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
1999                                 return;
2000                         }
2001
2002                         ns->regs.count = 0;
2003                         switch (NS_STATE(ns->nxstate)) {
2004                                 case STATE_ADDR_PAGE:
2005                                         ns->regs.num = ns->geom.pgaddrbytes;
2006                                         break;
2007                                 case STATE_ADDR_SEC:
2008                                         ns->regs.num = ns->geom.secaddrbytes;
2009                                         break;
2010                                 case STATE_ADDR_ZERO:
2011                                         ns->regs.num = 1;
2012                                         break;
2013                                 default:
2014                                         BUG();
2015                         }
2016                 }
2017
2018                 /* Check that chip is expecting address */
2019                 if (!(ns->nxstate & STATE_ADDR_MASK)) {
2020                         NS_ERR("write_byte: address (%#x) isn't expected, expected state is %s, "
2021                                 "switch to STATE_READY\n", (uint)byte, get_state_name(ns->nxstate));
2022                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2023                         return;
2024                 }
2025
2026                 /* Check if this is expected byte */
2027                 if (ns->regs.count == ns->regs.num) {
2028                         NS_ERR("write_byte: no more address bytes expected\n");
2029                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2030                         return;
2031                 }
2032
2033                 accept_addr_byte(ns, byte);
2034
2035                 ns->regs.count += 1;
2036
2037                 NS_DBG("write_byte: address byte %#x was accepted (%d bytes input, %d expected)\n",
2038                                 (uint)byte, ns->regs.count, ns->regs.num);
2039
2040                 if (ns->regs.count == ns->regs.num) {
2041                         NS_DBG("address (%#x, %#x) is accepted\n", ns->regs.row, ns->regs.column);
2042                         switch_state(ns);
2043                 }
2044
2045         } else {
2046                 /*
2047                  * The byte written is an input data.
2048                  */
2049
2050                 /* Check that chip is expecting data input */
2051                 if (!(ns->state & STATE_DATAIN_MASK)) {
2052                         NS_ERR("write_byte: data input (%#x) isn't expected, state is %s, "
2053                                 "switch to %s\n", (uint)byte,
2054                                 get_state_name(ns->state), get_state_name(STATE_READY));
2055                         switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2056                         return;
2057                 }
2058
2059                 /* Check if this is expected byte */
2060                 if (ns->regs.count == ns->regs.num) {
2061                         NS_WARN("write_byte: %u input bytes has already been accepted, ignore write\n",
2062                                         ns->regs.num);
2063                         return;
2064                 }
2065
2066                 if (ns->busw == 8) {
2067                         ns->buf.byte[ns->regs.count] = byte;
2068                         ns->regs.count += 1;
2069                 } else {
2070                         ns->buf.word[ns->regs.count >> 1] = cpu_to_le16((uint16_t)byte);
2071                         ns->regs.count += 2;
2072                 }
2073         }
2074
2075         return;
2076 }
2077
2078 static void ns_nand_write_buf(struct nand_chip *chip, const u_char *buf,
2079                               int len)
2080 {
2081         struct nandsim *ns = nand_get_controller_data(chip);
2082
2083         /* Check that chip is expecting data input */
2084         if (!(ns->state & STATE_DATAIN_MASK)) {
2085                 NS_ERR("write_buf: data input isn't expected, state is %s, "
2086                         "switch to STATE_READY\n", get_state_name(ns->state));
2087                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2088                 return;
2089         }
2090
2091         /* Check if these are expected bytes */
2092         if (ns->regs.count + len > ns->regs.num) {
2093                 NS_ERR("write_buf: too many input bytes\n");
2094                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2095                 return;
2096         }
2097
2098         memcpy(ns->buf.byte + ns->regs.count, buf, len);
2099         ns->regs.count += len;
2100
2101         if (ns->regs.count == ns->regs.num) {
2102                 NS_DBG("write_buf: %d bytes were written\n", ns->regs.count);
2103         }
2104 }
2105
2106 static void ns_nand_read_buf(struct nand_chip *chip, u_char *buf, int len)
2107 {
2108         struct nandsim *ns = nand_get_controller_data(chip);
2109
2110         /* Sanity and correctness checks */
2111         if (!ns->lines.ce) {
2112                 NS_ERR("read_buf: chip is disabled\n");
2113                 return;
2114         }
2115         if (ns->lines.ale || ns->lines.cle) {
2116                 NS_ERR("read_buf: ALE or CLE pin is high\n");
2117                 return;
2118         }
2119         if (!(ns->state & STATE_DATAOUT_MASK)) {
2120                 NS_WARN("read_buf: unexpected data output cycle, current state is %s\n",
2121                         get_state_name(ns->state));
2122                 return;
2123         }
2124
2125         if (NS_STATE(ns->state) != STATE_DATAOUT) {
2126                 int i;
2127
2128                 for (i = 0; i < len; i++)
2129                         buf[i] = ns_nand_read_byte(chip);
2130
2131                 return;
2132         }
2133
2134         /* Check if these are expected bytes */
2135         if (ns->regs.count + len > ns->regs.num) {
2136                 NS_ERR("read_buf: too many bytes to read\n");
2137                 switch_to_ready_state(ns, NS_STATUS_FAILED(ns));
2138                 return;
2139         }
2140
2141         memcpy(buf, ns->buf.byte + ns->regs.count, len);
2142         ns->regs.count += len;
2143
2144         if (ns->regs.count == ns->regs.num) {
2145                 if (NS_STATE(ns->nxstate) == STATE_READY)
2146                         switch_state(ns);
2147         }
2148
2149         return;
2150 }
2151
2152 static int ns_exec_op(struct nand_chip *chip, const struct nand_operation *op,
2153                       bool check_only)
2154 {
2155         int i;
2156         unsigned int op_id;
2157         const struct nand_op_instr *instr = NULL;
2158         struct nandsim *ns = nand_get_controller_data(chip);
2159
2160         ns->lines.ce = 1;
2161
2162         for (op_id = 0; op_id < op->ninstrs; op_id++) {
2163                 instr = &op->instrs[op_id];
2164                 ns->lines.cle = 0;
2165                 ns->lines.ale = 0;
2166
2167                 switch (instr->type) {
2168                 case NAND_OP_CMD_INSTR:
2169                         ns->lines.cle = 1;
2170                         ns_nand_write_byte(chip, instr->ctx.cmd.opcode);
2171                         break;
2172                 case NAND_OP_ADDR_INSTR:
2173                         ns->lines.ale = 1;
2174                         for (i = 0; i < instr->ctx.addr.naddrs; i++)
2175                                 ns_nand_write_byte(chip, instr->ctx.addr.addrs[i]);
2176                         break;
2177                 case NAND_OP_DATA_IN_INSTR:
2178                         ns_nand_read_buf(chip, instr->ctx.data.buf.in, instr->ctx.data.len);
2179                         break;
2180                 case NAND_OP_DATA_OUT_INSTR:
2181                         ns_nand_write_buf(chip, instr->ctx.data.buf.out, instr->ctx.data.len);
2182                         break;
2183                 case NAND_OP_WAITRDY_INSTR:
2184                         /* we are always ready */
2185                         break;
2186                 }
2187         }
2188
2189         return 0;
2190 }
2191
2192 static int ns_attach_chip(struct nand_chip *chip)
2193 {
2194         unsigned int eccsteps, eccbytes;
2195
2196         if (!bch)
2197                 return 0;
2198
2199         if (!mtd_nand_has_bch()) {
2200                 NS_ERR("BCH ECC support is disabled\n");
2201                 return -EINVAL;
2202         }
2203
2204         /* Use 512-byte ecc blocks */
2205         eccsteps = nsmtd->writesize / 512;
2206         eccbytes = ((bch * 13) + 7) / 8;
2207
2208         /* Do not bother supporting small page devices */
2209         if (nsmtd->oobsize < 64 || !eccsteps) {
2210                 NS_ERR("BCH not available on small page devices\n");
2211                 return -EINVAL;
2212         }
2213
2214         if (((eccbytes * eccsteps) + 2) > nsmtd->oobsize) {
2215                 NS_ERR("Invalid BCH value %u\n", bch);
2216                 return -EINVAL;
2217         }
2218
2219         chip->ecc.mode = NAND_ECC_SOFT;
2220         chip->ecc.algo = NAND_ECC_BCH;
2221         chip->ecc.size = 512;
2222         chip->ecc.strength = bch;
2223         chip->ecc.bytes = eccbytes;
2224
2225         NS_INFO("Using %u-bit/%u bytes BCH ECC\n", bch, chip->ecc.size);
2226
2227         return 0;
2228 }
2229
2230 static const struct nand_controller_ops ns_controller_ops = {
2231         .attach_chip = ns_attach_chip,
2232         .exec_op = ns_exec_op,
2233 };
2234
2235 /*
2236  * Module initialization function
2237  */
2238 static int __init ns_init_module(void)
2239 {
2240         struct nand_chip *chip;
2241         struct nandsim *ns;
2242         int retval = -ENOMEM, i;
2243
2244         if (bus_width != 8 && bus_width != 16) {
2245                 NS_ERR("wrong bus width (%d), use only 8 or 16\n", bus_width);
2246                 return -EINVAL;
2247         }
2248
2249         ns = kzalloc(sizeof(struct nandsim), GFP_KERNEL);
2250         if (!ns) {
2251                 NS_ERR("unable to allocate core structures.\n");
2252                 return -ENOMEM;
2253         }
2254         chip        = &ns->chip;
2255         nsmtd       = nand_to_mtd(chip);
2256         nand_set_controller_data(chip, (void *)ns);
2257
2258         chip->ecc.mode   = NAND_ECC_SOFT;
2259         chip->ecc.algo   = NAND_ECC_HAMMING;
2260         /* The NAND_SKIP_BBTSCAN option is necessary for 'overridesize' */
2261         /* and 'badblocks' parameters to work */
2262         chip->options   |= NAND_SKIP_BBTSCAN;
2263
2264         switch (bbt) {
2265         case 2:
2266                 chip->bbt_options |= NAND_BBT_NO_OOB;
2267                 /* fall through */
2268         case 1:
2269                 chip->bbt_options |= NAND_BBT_USE_FLASH;
2270                 /* fall through */
2271         case 0:
2272                 break;
2273         default:
2274                 NS_ERR("bbt has to be 0..2\n");
2275                 retval = -EINVAL;
2276                 goto error;
2277         }
2278         /*
2279          * Perform minimum nandsim structure initialization to handle
2280          * the initial ID read command correctly
2281          */
2282         if (id_bytes[6] != 0xFF || id_bytes[7] != 0xFF)
2283                 ns->geom.idbytes = 8;
2284         else if (id_bytes[4] != 0xFF || id_bytes[5] != 0xFF)
2285                 ns->geom.idbytes = 6;
2286         else if (id_bytes[2] != 0xFF || id_bytes[3] != 0xFF)
2287                 ns->geom.idbytes = 4;
2288         else
2289                 ns->geom.idbytes = 2;
2290         ns->regs.status = NS_STATUS_OK(ns);
2291         ns->nxstate = STATE_UNKNOWN;
2292         ns->options |= OPT_PAGE512; /* temporary value */
2293         memcpy(ns->ids, id_bytes, sizeof(ns->ids));
2294         if (bus_width == 16) {
2295                 ns->busw = 16;
2296                 chip->options |= NAND_BUSWIDTH_16;
2297         }
2298
2299         nsmtd->owner = THIS_MODULE;
2300
2301         if ((retval = parse_weakblocks()) != 0)
2302                 goto error;
2303
2304         if ((retval = parse_weakpages()) != 0)
2305                 goto error;
2306
2307         if ((retval = parse_gravepages()) != 0)
2308                 goto error;
2309
2310         nand_controller_init(&ns->base);
2311         ns->base.ops = &ns_controller_ops;
2312         chip->controller = &ns->base;
2313
2314         retval = nand_scan(chip, 1);
2315         if (retval) {
2316                 NS_ERR("Could not scan NAND Simulator device\n");
2317                 goto error;
2318         }
2319
2320         if (overridesize) {
2321                 uint64_t new_size = (uint64_t)nsmtd->erasesize << overridesize;
2322                 struct nand_memory_organization *memorg;
2323                 u64 targetsize;
2324
2325                 memorg = nanddev_get_memorg(&chip->base);
2326
2327                 if (new_size >> overridesize != nsmtd->erasesize) {
2328                         NS_ERR("overridesize is too big\n");
2329                         retval = -EINVAL;
2330                         goto err_exit;
2331                 }
2332
2333                 /* N.B. This relies on nand_scan not doing anything with the size before we change it */
2334                 nsmtd->size = new_size;
2335                 memorg->eraseblocks_per_lun = 1 << overridesize;
2336                 targetsize = nanddev_target_size(&chip->base);
2337                 chip->chip_shift = ffs(nsmtd->erasesize) + overridesize - 1;
2338                 chip->pagemask = (targetsize >> chip->page_shift) - 1;
2339         }
2340
2341         if ((retval = setup_wear_reporting(nsmtd)) != 0)
2342                 goto err_exit;
2343
2344         if ((retval = init_nandsim(nsmtd)) != 0)
2345                 goto err_exit;
2346
2347         if ((retval = nand_create_bbt(chip)) != 0)
2348                 goto err_exit;
2349
2350         if ((retval = parse_badblocks(ns, nsmtd)) != 0)
2351                 goto err_exit;
2352
2353         /* Register NAND partitions */
2354         retval = mtd_device_register(nsmtd, &ns->partitions[0],
2355                                      ns->nbparts);
2356         if (retval != 0)
2357                 goto err_exit;
2358
2359         if ((retval = nandsim_debugfs_create(ns)) != 0)
2360                 goto err_exit;
2361
2362         return 0;
2363
2364 err_exit:
2365         free_nandsim(ns);
2366         nand_release(chip);
2367         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2368                 kfree(ns->partitions[i].name);
2369 error:
2370         kfree(ns);
2371         free_lists();
2372
2373         return retval;
2374 }
2375
2376 module_init(ns_init_module);
2377
2378 /*
2379  * Module clean-up function
2380  */
2381 static void __exit ns_cleanup_module(void)
2382 {
2383         struct nand_chip *chip = mtd_to_nand(nsmtd);
2384         struct nandsim *ns = nand_get_controller_data(chip);
2385         int i;
2386
2387         free_nandsim(ns);    /* Free nandsim private resources */
2388         nand_release(chip); /* Unregister driver */
2389         for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
2390                 kfree(ns->partitions[i].name);
2391         kfree(ns);        /* Free other structures */
2392         free_lists();
2393 }
2394
2395 module_exit(ns_cleanup_module);
2396
2397 MODULE_LICENSE ("GPL");
2398 MODULE_AUTHOR ("Artem B. Bityuckiy");
2399 MODULE_DESCRIPTION ("The NAND flash simulator");